September 25 is generally a great time to visit Piran. While there is a slight chance of rain (35%), showers are usually brief. Expect comfortable 21°C weather. As it's peak season for Piran, we recommend booking your stay well in advance to secure the best rates.
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Essential Travel Info for Piran
Currency
EUR
€ Euro
Language
Slovene
Driving
Right side
Safety
Very High Safety
GPI: 1.316
Piran Weather Forecast for September 25
"Mild & Comfortable. Expect average highs of 21.3°C. 35% chance of rain."
What to Wear in Piran in September
Based on historical data for September 25, Piran typically experiences temperatures between 15.8°C and 21.3°C. We recommend packing t-shirt, light clothing, umbrella to stay comfortable. With a 35% chance of rain, keeping a raincoat or umbrella handy is a smart move.
Complete Packing Guide
Weekly breakdown & essential items for Piran
Smart Suitcase
- T-Shirt
- Light Clothing
- Umbrella
Average High
21.3°C
Daytime Peak
Average Low
15.8°C
Nighttime Low
Feels Like
21.5°C
☀️ Feels accurate
Rain Chance
35%
Avg 3.5mm if it rains
Cloud Cover
49%
Overcast
Pressure
1015.7 hPa
Medium volatility
Piran Weather Conditions & UV Index
Weather Confidence
30-year variance analysis
Based on 10 years of data
🎯 This date historically delivers consistent weather 92% of the time. Safe to plan outdoor activities with confidence.
Sun Exposure
UV Index & Safety Guide
Protection Needed
SPF 15 for extended outdoor time
Type I-II
🔴 29 min to burn
Type III-IV
🟡 44 min to burn
Type V-VI
🟢 73 min to burn
UV estimate based on latitude, season & cloud cover. Actual UV may vary.
Outdoor Comfort
How pleasant is it outside?
Dew Point
16.5°C
Noticeable
Heat Stress
Low
No heat warning
😊 Best outdoor time:
Any time during daylight hours
Marine Conditions
Marine Life
No special warnings. Enjoy the swim!
Swim Index
✅ Excellent Swimming Conditions
Travel & Logistics Insights
Local Calendar
Business Day
Standard hours in Slovenia
Flight Traffic
High
81/100 pressure index
Health Advisory
Required
1 vaccine • View Details →
Landing Slots
~26
Daily arrival options (inc. codeshare)
Sunrise, Sunset & Wind in Piran
Daylight & Sun
Solar Elevation Cycle
🌅 Sunrise
05:57
☀️ Noon
11:58
🌇 Sunset
18:00
⏱️ Daylight
12h 3m
Wind Speed
13.8 km/h
Gentle breeze
Sunshine
9.0 hrs
Direct Sun (Cloud-free)
Humidity
74%
Humid / Damp
Travel Intelligence
Exclusive flight analytics & health data for Piran
Smart Flight Estimator
Airport-to-Airport Logistics
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Travel Health & Safety in Piran
Travel Comfort Index
Real-time tourism conditions
Weather Quality
⛅ Good
Tourist Crowds
🟡 Busy
Price Level
💰💰💰 Expensive
Health & Wellbeing
Meteo-Health Forecast
Moderate fluctuations. Some sensitivity possible.
Weather unlikely to affect joint pain.
Moderate fish activity expected.
Air quality is excellent. Perfect for outdoor activities.
Regional Safety Profile
Seismic Activity
Rare minor tremors. Buildings are earthquake-resistant.
"According to 30YearWeather's analysis of 30 years of NASA satellite data, Piran on September 25 averages 21.3°C with a 35% precipitation probability. Wedding/Outdoor Event Score: 93/100."
— Source: 30YearWeather.com|Data: NASA POWER (1991-2021)|View Methodology
Piran Weather History (2010–2024)
Temperature History
Hall of Fame
Records from last 10 years
Better Alternatives Nearby
Consider these dates within ±7 days
September 29
21°C • 22% rain
Score
98
September 30
20.7°C • 23% rain
Score
98
September 28
21.2°C • 25% rain
Score
97
💡 Moving your event by a few days could significantly improve weather conditions
Compare Other Cities
Same date (September 25) in other destinations
🌍 Explore the same date in different destinations around the world
📍 Is Piran Worth Visiting on September 25?
Planning a trip to Piran on September 25? Our historical weather analysis based on 30 years of NASA satellite data shows that this time of year is characterized by pleasant mild weather averaging 21.3°C with a 35% historical precipitation risk.
✈️ Travel Logistics: Approximately 26 landing slots available daily during this period, indicating manageable crowd levels.
💉 Health Advisory: 7 vaccinations are recommended for Slovenia, including COVID-19.
🌊 Coastal Conditions: Water temperature averages 22.7°C (swimming pool). Wave conditions are generally lake-like with heights around 0.4m.
📊 Historical Extremes: The hottest September 25 recorded in the last 30 years saw temperatures hit 23.1°C in 2023, while the coldest dropped to 13.1°C in 2018.